Why is naruto last name is uzomaki while his dads last name is kamikazy?

Minato Namikaze (Fourth Hokage) was a great hero of the Third Great Ninja War. He assassinated many Iwagakure shinobi, and therefore had many enemies. That is why Naruto's surnname is his mother's rather than his father's; if Iwa knew that he was the Fourth's son, they would probably try and kiddnap him.